According to Philostratus, writing a century and a half after the event, once when Musonius was lying chained in the prison of Nero, his friend the notorious Apollonius of Tyana secretly communicated with him, inquiring what he might do to help release him. Musonius' reply was a brief acknowledgment of Apollonius' thoughtfulness and a polite but firm refusal of assistance, Thereupon Apollonius answered in one terse sentence, "Socrates the Athenian refused to be released by his friends, and consequently went to trial and was put to death." To which Musonius answered, "Socrates was put to death because he did not take the trouble to defend himself, but I intend to make my defence. Farewell." A generation later, Origen, in his apology for Christianity, the treatise Contra Celsum, named the two men who in the judgment of some people stood out as models of the highest type of life, the two saints, as it were, of the pagan world, Socrates and Musonius. In the fourth century, the emperor Julian wrote a letter to commend the high-priest Theodorus for his meretorious behaviour when he was insolently abused by the governor of Greece. Among other compliments, he said that Theodorus' complete lack of resentment was comparable to Socrates' equanimity under an unjust condemnation, while his desire to aid the city where he had suffered could be compared to Musonius' generous efforts in behalf of Gyara where he had been exiled.
In these three instances, the names of the Greek and the Roman philosophers are linked together as preeminent examples of men who professed the highest ethical standards and lived lives in harmony with their teachings. From these implied comparisons, given simply, without any explanatory material to lend them persuasive force, one may suspect that the comparison was not at all strained, but was in fact one which was current and familiar. And now, centuries later, when much of the material which might have made the comparison more obvious has been lost, a modern scholar does not hesitate to call Musonius "the Roman Socrates."
To us who might find it difficult to name a point in our lives when the name Socrates was new to us, and who have only a vague recollection of Musonius as one of the Stoic martyrs in the pages of Tacitus, the juxtaposition of the names may seem extravagant. The obscurity which has dimmed the name and reputation of Musonius is one of the unfortunate accidents of historical record, for even the extant testimonia of ancient writers, meagre as they are, lead us to the conclusion that Musonius was a much more compelling personage than his surviving works permit us to suspect, in fact one of the most significant figures of his age. Although a professor of Stoic doctrine, Musonius was by no means restricted by sectarian boundaries; his teachings were his own humanitarian interpretation of the fundamental principles regulating human conduct, truly the fruit of a good life and the expression of a great personality. In the mere fact of standing forth as the spiritual and ethical leader and "apostle of moral liberty" to his own and succeeding generations, Musonius is rightly compared to Socrates. But the exactness of the comparison becomes vivid and impressive when one notes how numerous are the points of similarity suggested by a consideration of the life of Musonius, his aims and methods, and the content and temper of his teachings.
Perhaps the least significant, if the most definite, point of similarity is that, though both men spent their lives teaching, they were so indifferent to preserving their thoughts that they made little effort to commit them to writing. There is a legend of some γράμματα of Musonius, but it is almost as unfounded as the tale of Socrates' writings. Apparently some contemporary record of hie teachings was made, but the manner and instrument of that original recording and the subsequent transmission of his words is far from clear. The fragments which we have were preserved among the works of other authors and were not collected until 1822 when they were first brought together by the Dutch scholar, I. V. Peerlkamp. This small collection of discourses and sayings may be divided into two groups. The first group, representing the bulk of the work, consists of twenty-one moral discourses, conversations, or διατριβαί, which are preserved only in the anthologies of Stobaeus. For all those discourses except one, Stobaeus gives the title Μουσωήον εκ τον..., but the fifth discourse differs in having the title Αυκίου εκ τών Μουσωνίου.... Yet the oneness of style and spirit, and the fact that all are assigned to Musonius have led scholars to consider all twenty-one essays as reports of his discourses made by one Lucius. The frequent recurrence of phrases like, "Such were the opinions Musonius expressed at that time" make it evident that this Lucius was a pupil of Musonius, and one specific reference in which Musonius speaks as an exile to an exile reveals that Lucius too suffered during his teacher's first banishment. Other than that it has been impossible to identify Lucius beyond saying that he was not the Lucius of Apuleius or Lucian or the commentator on the Categories of Aristotle from whom Simplicius freely borrowed. All of the discourses were probably published some time after Musonius' death.